Transcript for Malaysia Airlines Mystery: The Disappearance of Flight 370

Good evening and we begin with the flight disappearing in midair as it flew to beijing. This is the flight tracker that showed the plane taking off from Malaysia. You can see some of the other planes in the sky. Take a closer look. Right in the middle is flight 370. The tracker showing it flying at 35,000 feet. Suddenly the track stops. The data flight from the communication from the cockpit gone. The altitude on the tracker suddenly plummeting to zero. Tonight the images emerging from the airport in beijing. Families waiting and learning something had gone terribly wrong. A man putting his hand to his forehead. A loved one there holding on to him. Back when the plane took off, this image of a woman on the phone as the shock set in as well. We have team coverage beginning with ABC at the beijing airport. Reporter: Good evening. Yes, this has been a very difficult time for these family members and these friends of those who were supposed to land here in beijing on that plane. But it didn't happen. Searchers are focusing on two oil slicks. One, 12 miles long spotted in the south China sea. Between Malaysia and Vietnam. The U.S. Is sending this destroyer and a sophisticated radar plan to help. But there have been no signs of wreckage or debris. The disappearance of the flight with 239 people onboard is a baffling and tragic mystery. We do know at 12:41:00 A.M. Local time Malaysia airlines flight 370 a Boeing 777 takes off. 2:40 A.M. The plane is cruising at 35,000 feet when it loses radar contact where the sea meets the gulf of Thailand. No distress call is received. 6:30 A.M. Family members await. Two hours go by before the plane is declared missing. No use. No nothing. Still waiting. Reporter: At this hotel room family members gathered in tears. I don't want to live. What is the point of me being alive says this mother who's 40-year-old son was on boaboard the plane. Officials came out to talk, hundreds of people had poured in creating a dangerous situation in the hotel. Out of control here. I can't even believe this. We are working with authorities who are activated the search and rescue -- Reporter: There have been no claims of terrorism. But reports say two passengers on the plane were traveling on pass ports stolen from european travelers. Three U.S. Citizens were onboard. And two children of Chinese parents. The only U.S. Adult is thought to be an executive who worked in Malaysia. Two-thirds of the passengers were Chinese. The rest from 13 other countries. The captain was very experienced having flown over 30 years and 18,000 hours from Malaysia airlines. It is Sunday morning. The family members and friends are waiting for more information about exactly what happened on that plane. But it is taking some time.

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